Railway-car driving mechanism.



2 SHEETSSHEF l.

Patented Sept. 18, 1917.

@m ATTORNEY APPLICATION FILED MAR. I7. 1916.

C H CALKINS RAILWAY CAR DRIVING MECHANISM.

C. H. CALKINS.

RAILWAY CAR DRIVING MECHANISM.

1,240,419: APPLICATION FILED MAR. 17, 1916. Patentedsept. 18,1917.

2 SHEETS-SHEET 2.

rrnn srarns Parana orrrcn CHA LES H. cALKINs, or LUDLOW, MASSACHUSETTS, ASSIGNOR TOBAUSH MACHINE 'roon COMPANY, A CORPORATION or MASSACHUSETTS.

Y RAILWAY-can DRIVING MECHANISM.

Specification of Letters Patent. Patented Sept. 18, 1917.

- Application filed March 17, 1916. Serial No. 84,855.

To all whom it may concern:

Be it known that 1, CHARLES H. CALKINS, a citizen of the United States, residing in Ludlow, Massachusetts, have invented certain new and useful Improvements in Rail way-Car Driving Mechanism, of which the following is a specification.

This invention aims to provide a new driving mechanism for railway cars where by a great reduction of speed between the motor and the driven wheels can be secured in a small space with very few parts, with less noise than previous driving mechanisms make and with great efficiency and whereby also a high speed and comparatively light,

motor may be used. Other points of ad vantage are referred to hereinafter.

The accompanying drawings illustrate an embodiment of the invention.

Figure 1 is a plan of the principal parts of a railway car truck with. the improved driving mechanism applied thereto;

Fig. 2 is a side elevation of the same partly in section as indicated by. theline 22 of Fig. l; l.

Fig. 3 is a side elevation of one of the axles showing thedriving gear in section;

Fig. 4 is a sectional view approximately on the line44 of Fig. 3.

Referring now to the embodiment of the invention illustrated, this represents a-singlc truck street railway car of a known type. The wheels A are driven by'shafts B which at their outer ends support journal boxes C which carry side rails D. The weight of the car comes directly on longitudinal bars E which are supported through intermediate leaf springs F upon theends of the rails D and through intermediate coiled springs G upon flanges on the bottom of the journal boxes; the bars E being stiffened by truss rods H, H connected at their ends to the bars E and connected thereto at intermediate points by rods J which pass through the coiled springs.

The wheel shafts are each in two sections B and B and are extended through a tubular axle K which is transversely divided and carried on hearings on the wheel shaft as hereinafter described, so that each wheel shaft carries the weight of the hollow axle and rotates within the same. The hollow axle may be braced by diagonal rods such as L and M, Fig. 3, integral therewith or fastened thereto in any suitable way. Each wheel Acarries an inside flange N for en gagement by a brake-shoe.

The motor 0 is preferably of the electric Ripe, but not necessarily. It is supported by anges P of its casing resting on supporting bars Q which at their ends are supported on the hollow axles K. This motor is arranged with its shaft R extending longitudinally of the car. The opposite ends of the motor shaft are connected to a flexible shaft coriprising an intermediate portion S connected by universal joints T to the driving gears. Each axle has at its center a gear casing U divided transversely as shown for convenience in assembling and shaped to inclose at thetop a worm V on a shaft W which is connected to the adjacent universal joint T.

Driven by the worm V is a worm gear X, the

hub Y of which forms bearings for the two separate sections B, B of the wheel shaft, the. hub Y being free to rotate about the shaft sections. Ball bearings Z are interposed between the hub. Y and the sections of the tubular axle K, so that the hub is free to rotate therein. Carried within the hub Y of the worm gear are spiral gears a mounted on radial spindles b so as to be carried bodily around with the worm gear X. On opposite sides of each spiral gear a, and in en-v gagelnent therewith are spiral gears c and d. The gear 0 is in turn engaged with a spiralv gear 6 on one of the shaft sections B; and the gear (Z is engaged with a corresponding sp'iralgeanf on the-opposite shaft section B. Each shaft section B is squared or otherwise splined into its gear, 6 and f re Spectively, thus providing a semi-floating rear axle construction. The shaft sections B, B are permanently attached to the wheels A. Therefore, by jacking up the car, any wheel A with its shaft section can be withdrawn endwise out of the axle without disturbing the mechanism. The spiral differential gearin shown is of a known type, such as is descri ed more fully for example in Patent No. 1,090,082 of March 10, 1914 to Muehl. The invention may be used, however, with any usual or suitable style of spiral differential gearing, or in fact with any ordinary spur or bevel differential gearing, or without differential. In the last case a single integral driving shaft would be used for both traction wheels of a pair and the worm gear X would be mounted directly on the driving shaft. I have used the term small space and with only two parts.

wheel shaft to include either an unbroken shaft for a pair of wheels or a shaft in two sections, one for each wheel. The spiral clifferential gearing is preferred, however, for communicating the motion of the worm gear X to the driven shaft sections because it has not only the advantage of permitting the opposite traction wheels to advance at different rates of speed as the car goes around a curve, but will drive wheels at both sides at all tin1es,so that where one rail may be slippery the wheel will not spin around while the opposite wheel remains unmoved.

The worm V and gear X by which the wheel shafts are driven permits of a great reduction of speed in the smallest possible space. For example, with the proportions illustrated a reduction of six to one may be effected, giving a speed of thirty'miles per hour to the car with a motor making two thousand revolutions per minute. With the bevel or spur gears ordinarily used for driving street cars the designer has generally to choose between two difficulties. In one case the pinion must be too small or the gear too large to go in the permitted space; in the other case two sets of gears must be used with an increased complication and cost. vVith worm gearing arranged as shown a great reduction may be obtained at once in a The worm drive has a great advantage over the ordinary spur or driving gear used on street cars in the matter of noise. The worm drive is practically silent and does "not become noisy with ear or with increased speed. In the ordinary gearing used on street. cars the noise is always great and becomes greater as the gears wear and an especially great nuisance at high speeds. I Vhere a difierential is introduced between the worm gear and the shaft sections the car can go around curves more smoothly and without the grinding of the wheels on the rails which is seriously objectionable both because of the noise and wear on wheels and rails.

In efliciency, worm gearing when well designed has a substantial advantage over spur Copies of this patent may be obtained for and bevel gearing. Perhaps the most important advantage is the possibility of using for such comparatively slow speed vehicles as street railway cars a high speed motor or a higher speed motor than those heretofore possible with a consequent reduction in size and weightof the motor and a more efficient where one rail is elevated, the front axle will be warped relatively to the rear axle, but the movement will take place around the central shaft and will be'taken up at the point of engagement of the worm with its worm gear and the motor and driving mechanism will.

be practically unaffected by the warped tion of the two axles.

Various modifications in the separate parts of themechanism and in the arrangement thereof may be made by'those skilled in the art without departing from the invention as defined in the following claim.

What I claim is- A railway car driving mechanism including in combination a high speed motor 0, two pairs of traction wheels A, separately rotatable wheel shafts B turning said wheels, saidmotor being located between the front pair and the rearnpair of wheels and having a shaft R extending lengthwise .of the car, a pair of flexible shafts S T extending lengthwise in opposite directions from the ends of the motor shaft and connected thereto, a worm V en aged and driven by each of said flexible sha ts, aworm gear X engaged posiby said worm and driven thereby at a my name.

' CHARLES H. CALKINS.

five cents each, by addressing the commissioner of Patent Washington, D. G. 1 

